Rowing practices are predicated on three days on the water:
Day 1 workouts are always longer pieces at progressively increasing rates as the weeks go by. They are designed to make rowers move the boats at lower rates as efficiently as possible. Note that the pieces vary in rate from 22 in the 2nd week to 28 in the 6th week. Each stroke is to be taken at a sustainable high pressure.
Day 2 workouts are time trials with a different technical focus each week. They provide a base for comparison and are also undertaken with rates that vary from 20 in the second week to 28 in the 6th week. Again, we are looking for technical movement with sustainable high pressure.
Day 3 workouts are to maintain skills at higher rates and to engage fast-twitch fibres. These are shorter and more intense pieces to engage anaerobic processes.
The workouts comprise a training plan - a road map - to get you from the sprint season to the head racing season. Follow the road map and you will get to your destination.